Synchronizing system



April 13 1926, 1,580,800

J. AUCHINCLOSS SYNCHRONI Z ING SYSTEM Filed May 24, 1924 26 50 l 8 6%? 1-29 0 g 9 0 i W 34 21k 36 22? as? TnVenbor: John Auchincloss;

Hi s Ammorna Patented Apr. 13, 1926.

UNITED STATES JOHN AUCHINCLOSS, OF SCOTIA, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COM- PATET PANY, A CORPORATION OF NEW YORK.

SYNGHRONIZING SYSTEM.

Application filed May 24, 1924. Serial No. 715,724.

To all whom it may concern:

Be it known that I, J orrN AUoHINoLoss, a citizen of the United States, residing at Scotia, in the county of Schenectady, State of New York, have invented certain new and useful Improvements in Synchronizing Systems, of which the following is a specilication.

My invention relates to synchronizing systems adapted for use where a source of electric current is required to be synchronized with a power bus or line arranged to be supplied with current from a plurality of sources and has for its object the provision of means for insuring that a source is not synchronized with one bus or line and then inadvertently connected to another bus or line.

Where a source of current is arranged to be synchronized with'and connected to any one of a plurality of buses, it frequently happens that the source is inadvertently connected to the wrong bus. In accordance with my invention, this diificulty is avoided by the provision of an arrangement wherein the synchronizing apparatus is so interlocked with the bus switches as to prevent the connection of the source to a bus with which it has not been synchronized.

My invention will be better understood on reference to the'following description when considered in connection with the accompanying drawing and its scope will be pointed out in the appended claims.

Referring to the drawing, Fig. 1 shows an arrangement in which my invention has been embodied; Fig. 2 shows a synchronizing plug adapted for use in connection with a machine which is running, and Fig. 3 shows a synchronizing plug adapted to be utilized in connection with the machine being synchronized. In order to simplify the drawing, the current sources have not been shown, and the power lines or buses and the conductors for connecting them to the current sources have been indicated by single lines. It will be apparent, however, that these single lines may represent a single or polyphase system.

The drawing shows a plurality of buses 1 and 2 arranged to be supplied with current from one'source through the ,line 3 and from another source through the line 4.

Current from the lin'e 3 is supplied througha main switch 5 either to the bus 1 through' through disconnect switch 10. While the main switches 5 and 8 are shown as of the air break type, it wi 1 be understood that oil switches are preferable in cases where the operating voltage and current are high enough to render the use of such switches desirable. Potential transformers 11 and 12 have their primary windings connected to the lines 3 and 4trespectively. The secondary windings of these transformers are each arranged to be connected to the synchronizing buses 13' and 1 1 through receptacles 15, 16, 17 and 18 and the running and starting plugs shown by Figures 2 and 3 respectively. The connections between the contact fingers of the running plug '19 and the starting plug are-indicated by dotted lines. A synchroscope 21 which may be of any suitable type is operatively associated with the'synchronizing buses 13 and 14.

' The synchronizing plugs 19 and 20 function both to connect the synchroscope 21 and synchronizing buses 13 and 14 to the transformers 11 and 12 and to control the connection of circuits through which the operating coils 22 and 23 ofmain switches 5 and 8 respectively are energized. This result is accomplished through locking buses 24 and 25 and interlock switches 26 and 27 28 and 29, 30 and 31, and 32 and 33, associated with the disconnect switches 7, 6, 10 and 9, respectively. Push buttons 34.- and 35 are pro- Vided for closing circuits by which the switch operating coils 22 and 23 are connected between the negative'control bus 36 and the positive control buses 37 and 38 respectively. A switch 39 shown as mounted in a cabinet 40 is arranged to interconnect the locking buses 24 and 25 for a purpose hereinafter explained.

For the purpose of explaining the operation of my invention, it will be assumed that the line 3 is connected to the bus 2 through main switch 5 and disconnect switch 7. Under these conditions, the interlock switches 26 and 27 are in their closed positions. In order to synchronize the source connected to line 4 with the bus 2, it is necessaryto insert the fingers of the runningplug 19 in the receptacle 15, to insert the fingers of the starting plug 20 in the receptacle 17 and to close the disconnect switch 10. When this is done, the right hand contact of the push button35 is connected to the negative control bus 36 through interlock switch 26, the running plug 19, locking bus 25, startingplug 20 and interlock switch 31. At the same time, the secondary winding of the transformer 11 is connected to the synchronizing bus 13 through the running plug 19 and the secondary winding of the transformer 12 is :onnected to the synchronizing bus. .14 through the starting plug 20. Under these conditions, the synchroscope will show when a state of synchronism exists between the sources associated with lines 3 and 4 respectively. When such a condition is .established, the push button 35 may be depressed to energize theoperatingcoil .23 and close the main line switch 8 through which the line 4 is connected to the bus 2.

The manner in which the mistake of connecting the line tto the bus 1 when it has been synchronized with the bus 2 is prevented will be readily imderstood if :it be assumed that the disconnect switches 7 and 9 are closed and the fingers of the running andstartingplugsare in the receptacles 15 and 17 respectively. Under these conditions, the secondary windings,of-transformers Hand 12 are connected to the synchronizing buses 13 andl t and the synchroscope will indicate when the sources associated with lines 3 and 4 are in synchronism with each other. Also, the locking-bus 25 is con nected to the negative control bus 36 through interlock switch 26 and plug 19, and to one contact of the interlock switch 21 through the plug 20, but since this interlock switch is open, it is impossible to energizetheswitch operating coil 23 by-depressing the push button35. It is thus impossible inadvertently to connectthe line a to the wrong bus when thefingers'of the starting plug 20 are in the receptacle 17 Where the bus 1 is known to be dead or in synchronism with the bus 2, emergencies may arise which make it desirable to connect the line 3 to bus 2 and the line 4: to bus 1, for example. It will be readilyund-erstood that this may be done by inserting the fingers oftheplug 20 in receptacle 18, opening the cabinet 10 and closing theswitch 39 to interconnect the locking buses2 l and 25. Under these conditions, current may be supplied to the operating coil 23 from the negative control bus 36 through interlock switch 26, running plug 19, locking buses25 and- 24, starting plug 20, interlock-switch 33, and push button 35.

The procedure to be followed in synchro nizing the line 4 with the bus 1 when the line .3 is connected to this bus willbe readily understood without further explanation. It will be observed that my invention is not limited to any particular number of buses and sources, but isgenerally useful where a plurality of sources are arranged to be interconnected with one another.

I have explained my invention by illus- 7 trating-and describing a certain specific embodiment thereof, but it will be readily understood by those skilled in the art that the arrangement of this embodiment may be modified.in'certain of its details. I, accordso ingly do not wish to be restricted'to the particular arrangement disclosed herein by way ofexample for the purpose of setting forth my invention in accordance with the patent statutes. The terms of the appended claims are, therefore, not restricted to the precise arrangement disclosed, but are intended to cover all changes within the true spirit and scope of my invention.

.lVhat I claim as new and desire to secure by LettersP-atent of the United States, is

1. The combination of a plurality of elec trical conductors, a plurality of alternating current sources, a plurality of disconnect switches each connected between one of said conductors and one of said sources, main switches each provided with an operating coil for controlling the connections between one of said sources and all of said conductors, control current supply means and means operable to connect one of said operating coils to said supply means only when a plurality of said disconnect switches are in closed position.

2. An electric power system wherein a plurality of current sources are arranged to be interconnected through disconnect switches and main switches each provided with an operating coil and wherein a synchroscope is provided for indicating a state of synchronism between said sources, coInprising means operable in response to actuation of said disconnecting switches for controlling the connections of said main switch operating coils, and means dependent on the connections of said synchroscope for controlling the connections of said coils.

3. A system of the class described comprisinga plurality of alternating current sources, main and disconnect switches for 1 interconnecting said sources, switch operating coils for actuating said main switches, a source of control current and circuits associated therewith for connecting said coils to said source, interlock means each operable to close a gap in one of said controlcircuits in'response to actuation of one of said disconnect switches, means for indicating a state of synchronism between said sources, means dependent on the connections between'said indicating means and said sources for closing a second gap in said control circuits, and means associated with said control circuits for connecting said coils to said source of control current.

4. The combination of aplurality of electrical conductors, a plurality of sources, a plurality of disconnect switches each connected between one of said conductors and one of said sources, main switches each pro vided with an operating coil forcontrolling the connections between one of said sources, and all of said conductors, means for indicating the relation between the frequencies of said sources, means operable in accordance with the positions of disconnect switches interposed in the connections of said sources or controlling the energization of said operating coils, and means operable to complete the connections of said operating coils only when said indicating means is connected to said sources.

5. The combination of a plurality of electrical conductors, a plurality of alternating current sources, a plurality of disconnect switches each connected between one of said conductors and one of said sources, main switches each provided with an operating coil for controlling the connections between one of said sources and all of said conductors, control current supply means, and means operable to connect one of said operating coils to said supply means only when a plurality of said disconnect switches interposed in the circuits of different sources are in closed position.

In witness whereof, I have hereunto set my hand this 23rd day of May, 1924:.

JOHN AUCHINCLOSS. 

